HVAC systems often include actuatable control devices such as dampers, valves, ventilation flaps, louvers, and/or other devices that, for example, help regulate the flow of air or gas. Many of these actuatable control devices have a rotary axle or shaft that, during use, is actuated by a drive unit such as an electric motor or the like. In a direct coupled actuator, a shaft adapter is configured to be placed over and coupled to the axle or shaft of the actuatable control device. Once installed, the drive unit may, through the shaft adapter, transmit a torque to the axle or shaft to actuate the actuatable control device.
In many applications, it is desirable to have the shaft adapter centered or coaxial with the axle or shaft of the actuatable control device when installed. However, the axles and/or shafts of many actuatable control devices come in a variety of sizes and/or shapes. Previously, it has been difficult and cumbersome to accommodate the various shaft sizes and/or shapes, particularly while maintaining the desired concentric arrangement between the shaft adapter and the axle or shaft of the actuatable control device. In some cases, a series of shaft adapters are produced, with each shaft adapter designed to accommodate a particular shaft size and/or shape. Alternatively, a series of separate inserts are provided, each designed to accommodate a particular shaft size and/or shape.
What would be desirable is an improved shaft adapter that can accommodate various sizes and/or shapes of axles or shafts of actuatable control devices, while providing a self centering arrangement between the shaft adapter and the axle or shaft of the actuatable control devices.